SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f5c609e9b7ec0e06d8ec12d725b8e23d97454637df8bab1e6aa6f76a1eecb31' 
  AND token = 'kjD9EHd2spwFwzzA0PWA39CF/lUzUg1Vz8Xd6ezamoE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}